Contact finger



Oct. 9, 192 1,686,643

0. P. scHusTER CONTACT mma Filed Aug. 7, 192

5'9. 3. Q 73 /s ee 2 25 3277 0 m F 2/ I INVENTOR 7 'ATTQ NEY Patented Och9,"1928 UNITED-STATES PATENT- OFFICE.

ozrro r. scnosrnn; or 1:01am Iawm, rmsynvurm, assmnon "ro wns'rmenousn ELECTBIG & mlmcc'runm 001mm, 4 conronnrrox or 2mm vanm.

. Application filed August 7, 1920. Serial in). 121,731. 1

My invention relates to contact fingers primarily designed for use in controllers;

The object of my invention, generally stated, is the provision of an adJustable contact fingerthat shall be simple and eflicient in op-l eration and capable of being readily and economically manufactured. e

A more specific object .oi my invention is to facilitate the taking apart of the contact finger to permit the removaland replacement of the parts subject to the greatest wear.

Another object of my invention is to provide for retaining the adjusting means in any mesposition in which it may be set-to space the contact-carrying. member and the base member in order to tension the spring.

@ther objects of the invention wilh'in part,

be obvious and, in part, appear hereinafter.

The invention accordingly is disclosed the embodiment thereof shown in the accompanying drawingand comprises the features of structure, combination of elements and ar indicated in the claims.

'rangement of parts which will be exemplified in the construction hereinafter set forth and the scope of the applicationof which will be For a fuller understanding of the nature and objects of the invention, reference should one embodiment of a contact finger constructy .es

shown in Fig. 5.

plan view of the contact Fig. 4 is asectiona l' along V Fig. 5' is'aview, in side-elevation, e resilient means provided for retainingthe contact member in position on the base; and

Fig. 6 is a bottonrplan view of the device Referring now to the drawing, the refer 'ence character 10 designates generally the base of a contact finger provided with an inclined end portion which is adapted for fastening to emboardor any other suppo rt usually provided in controllers or the like for hereinafter.

carrying contact fingers. .As illustrated, the .Since the object of member 11 has anbpening 12 drilled therein near its end for the reception of a bolt 13 that may be used for attaching it to a support.

As shown, a substantially straight mem ber 14 constitutes the main portion of the base member .10. In order to adapt the member 14 for the mounting oft-he contact-carrying member,-shown generally at 15, an opening 16 is. provided therein near the juncture of v thetvo sectionsfll and 14 of the base. Further, a slot 17 is cutin-the free end ofthe straight section of the base 10 for the reception of the outer end of the contact-carrying member 15. v

The contact-carrying member comprises a main body (portion 18, which is substantially straight, an two depending end portions 19 and 20. As will be observed b reference to Figures 1 to 4, inclusive, the epending end 19 is' provided with a small projection or tongue 21 that is shaped to fit'into the opening 16 in the base '10, and themember 20 is made narrow enough to fit'into the slot 17.

Hence, by the insertion of the projection 21 into the opening 16, and the depending endportion 20 in the slot17, the contact-carrying 4 member 15 ma be pivotallymounted on the base 10. Furt er the depending end 20 will serve to guide the: movement of the contactcarrying member 15 withinY'predetermined As illustrated in Fig. 3, the lower end 22 of the depending member19 is curved'to per-.

mit lateral oscillatory movement of the 'con-' tact-carrying member on the base. The oscil- .latory movement .of the contact-carrying member 15 is. not limited by the depending a I member 20, since the latter may be loosely mounted in the slot 17. A c

In order to retain the contacbcarryingmember 15 in position on the/base 10, a resilient unit is utilized. The construction of the latter is best illustrated inFig'1-5 which 25 and 26. ,"A head 27 is provided bn the up shows to comprise a pin 23011 which a.

24 is mounted. The spring is' re-- tained;in position on the pin by means of: -twoslidably mounted dish-shaped washers nve'ntion' for the replacement of parts-,th' resilient longitudinal-axis a permit detect mem:

means for retaining the contact-carrying,

member inpos'ition on the base is removabl mounted, so'ithat it may be detached .at wi It will be readil understood that many methods may be a opted for removably mounting the pin on the base. In this particular construction, the intermediate member 14 of the base is crimped to provide a substantially inverted-V-shapedsection 29,

and a slot extending longitudinally of the member 14 is punched therein for the reception of the end 28 of the pin 23.

her to' properly'set or 'adjiist itself to-make engagement throughout the .length of its contacting face.- Accordingly, a contact finger of this type will rea dilyeadjust itself during operation over uneven surfacesand the like.

In order to tear down the contact finger, the pin 23 is disengaged from the base 10 by pressing down and turning. The contactcarrier 15Amay-thei1 be removed. If the contact member 35 has-been so worn as to require replacement, it canbe readily detached by use of a'file. Since thecontact member When the head 28 of the pin is inserted through the slot 30 and turned through an angle of 90, the shoulders 31 of the pin will seat in the crimped section 29. Since the spring 24: is in tension, it will serve to retain the head of the pin.23 in position. In this manner, the pin is mountedto permit a certain oscillatory movement inevery direction,

to allow the contact/carrying member to take difierent positions. c.

Inorder to adjust the contact-carrying member 15 relative to the base 10, a set screw 32 is mounted in'the former. As will be ob 'tinual workingof the contact finger.

In setting the contact finger for operation, A

' the contact carrier 15 from the base 10 and to position the contact member 35 tov ride on the served, any adjustment of the set screw willvary the tension of the spring 24:. The head of the set screw 32 is made polygonal in shape, and a flat spring 33 is provided with a vertical section 34', which seats againstthe head of the 35. 3 tion to which it may be rotated;

set screw, is mounted on portion 20 of the contact-carrying member 15. Thespring 33 w11l serve to retain the set screw in any posi- A contact member or tip 35 is mounted on an extension 36 of the depending member 20. As shown, the contact member 35is provided wlth a shoulder 37 which abuts against the end of the contactecarrying member. In forming the contact member 35, a stud 38 1s providedthereon to serve in attaching it material, little difliculty is experienced in filing ofl? theriveted end-of the stud 38. In 1 such. constriictions, a riveted stud is prefmade from copper, brass or some such erably to? securing the contact tip 35, since a-bolt and, nut connection is unsuitable, because of its tendency to loosen with the conthe set-screw 32 is adjusted to properly space cooperating drum segment. If the drum segment has any raised portions, the contact carrier 15 may oscillate freely about a longitudi- 'nal axis extending through its inner end,

while the spring 24: continuously urges the contact member 35 toward the drum segment. Since certain changes maybe made in the above construction. and di flerent embodiments of the invention may be made without departing from'the scopethereof, it is intended that all matter contained in the above and not in a limiting sense. i

v to the contact-carrying member. In this particular construction, the stud is also used for mounting the spring 33 on the contact-carrymemberp a he contact member 35 is preferably made from some conducting material, such as copper or brass, but it may also be made from steel. Witha viewof establishing a good electrlcal connection between terminal and the contact member 35, a flexible laminated conductor. 39 is provided, one end being clamped between portion 36 of the contactcarrying member and the contact member 35. After the contact finger is mounted on a supporting rail or the like, the set-screw 32 may be adjusted to properly tension thespring 24. In this manner, the roper pressure between the contacting sur aces may be obtained.

. Assumingthat the drumcontact segment that engages the finger is uneven, the contactmember '15 will oscillate about a description or shown in the accompanying drawing shall .beointerpreted as illustrat ve I claim as my invention:

1-. In a contact finger, in combination, a base member, a contact-carrying member p votally mountedon the base member, resilient,

means for retaining the contact-carryin member in position on thebase member, said contact-carrying member havin an opening in its outer end, a contact mem er having a stud formed thereon, mounted on the contactcarrying member, thestud projecting through the opening and a shoulder 'formed on .the

end of the contact-carrying member toretain the contact member in a predetermined position.

2. In a contact finger, in combination, a base member, a contact-carrying member pivotally mounted on the base member, resilient Y means in a predetermined position, a contact 1 .ClOl) I cont-act member and disposed to engage the member provided with a stud mounted on the contact-carrying member, the stud projecting through .said opening, said stu being utilized to attach the spring member to the contact-carrying member.

3. In a contact finger, in combination, a

base member, a contact-carrying member pivotally mounted on the base member, said contact-carrying member having an opening in its outer end, resilient means. adapted to be removably mounted in the base member for' retaining the contact-ca ing member in position on the base me iiber, a set screw for adjusting the contact-carrying member relative to the base member, a s ring mounted on the contact-carrying memEer or retaining said set screw in position, a contact member provided with a stud mounted on the contact-carrying member, said stud projecting through the opening in the'contact-carrying member and engaging the spring to retain the latter in position, a shoulder provided on the contact member, said shoulder being disposed to engage the end of the contact-carrying member to retain the contact member ina predetermined position.

4. In a contact finger, in combination a base member, a contact-carrying member piv otally mounted on the base member, resihent means adapted to be removably mounted in the base member for retaining the contactcarrying member in position on the base mem-v ber, a set screw mounted in the contact member and disposed to engage the base member whereby said members may be set in any predetermined relative positions,a spring carriedby the contact-carrying member for retaining the set' screw in position, a "flexible conductor extending from the inner end of the base member to the outer end of the conname this 5th. day of 

